The government decision to approve plans for a third runway at Heathrow will be opposed by one of the broadest coalitions ever formed in Britain, ranging from government advisers to those threatening direct action, and including environment and development groups, local government, scientists and celebrities.

The largest organisation to oppose the scheme was the National Trust, with 3.5m members. It has several properties at risk of increased noise pollution, including Osterley Park which would expect a plane flying over it every 90 seconds. "The decision is a direct threat to the tranquility and possibility of escape from an increasingly hectic and urbanised environment that millions of people seek. More flights will significantly damage their quality of life," said Fiona Reynolds, director of the trust.

Major green groups, including RSPB, Greenpeace, Friends of the Earth and WWF, with a combined membership of more than 2.5m people, attacked the plan on climate change grounds. "Expanding Heathrow is a hammer blow for UK climate targets that will shatter Gordon Brown's reputation on the environment. This terrible decision will intensify opposition to the government's aviation strategy," said Andy Atkins, director of Friends of the Earth.

Oxfam, one of many international charities concerned with the effects of climate change on the world's poorest people, said it gave the wrong signal to the rest of the world about how serious the British government is about tackling climate change, in the year when a global deal must be struck in Copenhagen. "The third runway threatens to completely undermine the UK's attempts to position itself as a global leader in tackling climate change," said climate policy adviser Rob Bailey. "Millions of poor people around the world will question how serious the UK is in combating the problem."

The decision also drew criticism from some of the government's own advisers. Lord Chris Smith, chair of the government's pollution watchdog group, the Environment Agency, said he was "deeply concerned".

"Air quality in the area is already at breaking point. We will make sure that limits [introduced yesterday by the government] are strongly and rigorously enforced."

While the UK is the only nation with a legally binding target for greenhouse gas emissions, Smith said: "Serious questions must be asked about how the aim of reaching an 80% reduction in greenhouse gases by 2050 can still be achieved in light of this decision."

Jonathon Porritt, chair of the government's Sustainable Development Commission, said he was "horrified". "This is very regrettable decision ignoring the fact that govermnment does not have the data about the economic benefits and has not done a proper asessment of the impacts and on its climate change targets. It does not add up."

Strong local concerns were also expressed. London mayor Boris Johnson said: "This is a devastating blow for millions of Londoners. I will support a legal challenge should this prove to be the case." He was backed by more than 20 London local authorities, representing more than 2 million people, which said the decision would bring "mayhem" to areas near the airport.

Climate change activists from Plane Stupid and the Oxford-based Seeds for Change training collective have advised local residents on how to work in groups, what kind of direct action to take and how to handle police and security guards. "Many were quite elderly people who … said they could take the risk of being arrested," said Kathryn Tulip, one of the trainers.

"We will stop this runway using every peaceful means at our disposal," said Plane Stupid's Elizabeth Baines, one of 56 people who helped shut down Stansted airport last year.

Thousands more people yesterday signed up to become joint owners with Greenpeace and celebrities of an acre of land at the heart of the proposed runway development. Actor Emma Thompson, one of the owners said: "It's a real slap in the face to every citizen in this country who has been doing their best to cut back on their own emissions."